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This study is to investigate the phase stability, cold deformation, elastic strain recovery and mechanical properties of a new Ti-17Nb-6Ta-3Zr, at. %, alloy for biomedical applications. The alloy was produced by arc melting. A heavy cold-working up to 90 % was applied to the alloy to investigate the stability of the predominant β-bcc structure. Characterization of the deformed structures was performed by X-ray diffraction (XRD), hardness measurements and optical microscopy. Quasi-static compression testing was conducted to determine the yield stress for stress induced martensitic (SIM) transformation and the Young modulus. XRD analysis of the cold-worked structures revealed that α-martensite was induced after less than 5 % deformation. An outstanding combination of strength-elasticity properties with the yield strength of 600 MPa and a Young modulus of 37 GPa was achieved during the compression tests.

An additively manufactured M789 steel was deposited on wrought precipitation-hardening N709 steel to form a hybrid alloy using the laser powder bed fusion (LPBF) process. After tensile testing, failure in the as-printed (AP) state was detected in the M789 section with a peak strength of 1019 MPa, consistent with the nanoindentation measurement across the M789-N709 interface. The application of heat treatment of the hybrid alloy shifted the failure zone to the N709 alloy with a peak strength of 1600 MPa. The high strength of M789 after heat treatment was due to the formation of the η-phase during aging. A robust metallurgical bond was successfully formed between the two alloys since the fracture did not occur in the interface for both the AP and heat treated (HT) states during tensile testing.